Mars Moon Tracker Help
This form enables you to generate a Postscript file showing the
east-west motion of Mars' satellites within a specified time period.
The distance of each selected moon from the planet's axis is plotted in
units of either arcsec or Mars radii. Positive values correspond
to bodies on the "morning" (east) side of Mars and negative values by
the "evening" (west) side. In the diagram, the limbs of Mars are
indicated by a dark gray stripe down the middle.
The Moon Tracker tool also allows you to download an ASCII table
containing the numeric values that went into the diagram. The file
contains a single header line followed by the numbers. Columns are as
Modified Julian Date (UTC)
Projected equatorial radius of planet (arcsec)
Distance of first moon from planet's axis (arcsec)
Distance of second moon from planet's axis (arcsec)
2.6 (January 4, 2016):
Ported to new server.
2.7 (October 14, 2020):
2.8 (June 20, 2021):
The start and stop times (UTC) of the plot can be entered in a variety
of formats. For example, the following all parse to 0:01:02 UTC on July
If you want the gory details of how times are interpreted, click
- 1976-JUL-04 00:01:02.00
- July 4, 1976 12:01:02 am
- 12:01:02 am July 4, 1976
- 1976-07-04T00:01:02Z (PDS format)
- MJD 42963.00071759259
- JD 2442963.50071759259
Enter the time interval to be used for the tabulation as a number in the box,
and select the time unit from the choices provided. Start times and intervals
are rounded to the nearest minute.
Enter the numeric range and units of the horizontal axis. The value
you enter is actually half the width of the diagram; for example, if you
enter 10 Mars radii, then the axis will run from -10 to 10. Zero
always falls at the middle of the plot.
Enter a title for the plot in this box. It will appear centered above
Click on the box to the left of each moon that you wish to include in the
diagram and in the tabulation.
Mars Moon Tracker Form |
Node Tools |
Ring-Moon Systems Node Home
Last updated June 20, 2021.